[Reticular pattern in thin-section CT: from morphology to differential diagnosis]

Major constituents of a reticular pattern in thin-section CT are thickened interlobular and intralobular septa as well as honeycombing. When thickening of the interlobular septa or honeycombing are visible as predominant features, these patterns have a limited differential diagnosis. In this context, a detailed analysis of morphologic characteristics (e.g., smooth or nodular interlobular septal thickening) and of the pattern localisation (e.g., peripheral, basal and subpleural honeycombing) is required. Thickened intralobular septa, parenchymal bands, subpleural lines and the "interface sign" are all rather non-specific findings. However, if interpreted in the context of other CT findings, a differential diagnosis may also frequently be reported.